This invention relates to electromagnetic displays of the type described in U.S. Pat. Nos. 4,163,332; 5,185,600 wherein each pixel comprises a shutter vane rotatable between a first position in which it covers a back-illuminated diffuser and the pixel appears dark and a second position in which the diffuser is exposed side by side with a reflective face of the vane and the pixel appears bright. Displays of this type include a matrix of electromagnets, the magnetic fields of which act upon magnets attached to the vanes so as to rotate the vanes. The vanes and diffusers provide the visual aspect of the display. For maximum brightness when viewed outdoors, the vanes and diffusers are preferably colored with fluorescent pigment, such as fluorescent yellow. Such pigment is subject to fading. In particular, the present invention is concerned with providing a display in which the components affecting the visual aspect are on replaceable modules each common to an array of pixels. The modules exclude connectors,wiring, electronic components and electromagnets.